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View Poll Results: Are 4-stroke outboards 'there' yet?
Yes 4 13.33%
No 8 26.67%
Nearly 4 13.33%
2-Stroke 4 eva! 12 40.00%
An egg-whisk is an eggwhisk is an eggwhisk. Yawn. 1 3.33%
I'm holding out for hydrogen fuel cells! 1 3.33%
Voters: 30. You may not vote on this poll

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Old 26-07-2006, 12:29 PM   #21
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Quote:
Originally posted by TheOrs
This is the very engine that got me thinking about 4-stroke vs 2-stroke.

Mate had a Challenger 2000 with a 2-stroke Merc M-Jet 240HP, then swapped it for a newer, slightly smaller Challenger with the 215HP Rotax 4-stroke. Old boat had more 'Holeshot' but was 10mph slower & used 60 litres of fuel where the new one will use about 40 litres for the same time out and max out at nearly 60mph. I have to admit I was suprised at how good it was.

I

Yep, It's a cracking unit. My mate has just had a Riva Racing kit delivered from the States for his. Apparently the HP increases to nearly 300. Now that should be interesting
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Old 26-07-2006, 01:23 PM   #22
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My concern with 4 strokes is weight and size. They look huge compared to 2 strokes with equal horse power.

Does this mean that for people such as myself who have an older boat (ring 18) which has a maximum hp rating of 200HP (which is what we are running with at the mo), we would be unable to fit a 4 stroke equivalent due to size / weight.

If this is the case and we wanted to fit a 4 stroke, then what would be the max HP that could be fitted to a Ring / Phantom / Marshan 18 / 19 and of course 21??
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Old 26-07-2006, 02:10 PM   #23
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40Lb differenace between yamaha vmax 2 stoke and a four stroke 200HP. Is that a lot?
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Old 26-07-2006, 02:33 PM   #24
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300XS Stroker 505lbs (longshaft)

275 Varado 667 lbs (Standard)

2.5's circa 450 lbs



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Old 26-07-2006, 02:38 PM   #25
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Quote:
Originally posted by BluFin
300XS Stroker 505lbs (longshaft)

275 Varado 667 lbs (Standard)

2.5's circa 450 lbs
Granted the Varado is excessive, but you can see that in its size.
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Old 29-07-2006, 02:53 PM   #26
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Quote:
Originally posted by Matt
Torque is the problem. Jets can be designed to rev to the sky and don't need much torque to get them spinning, "slip" is incredibly high on a jet. The same motor coupled to a prop on a rib full of divers would struggle.
Yes; what you say ties in with the driving experience. The 4-stroke jet is a little slower out of the hole but I guess it gets the top end advantage 'cause at Vmax it's revving to about 8K.
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Old 30-07-2006, 05:35 AM   #27
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2 stroker's are King

YES!.....Still has to be a 2 stroker for me two,even though the old Xr2's are a load of old crap,'god bless'em, No afence.. (Been there and got the t shirt!)

The opimax 2 stroke XS's have sorted the feull brobs out,even being more economical than some big 4stroker's.

But I still love the sound of the xr2, when I, just like ya self was'nt fixing it. I must have been band off every jet ski lake in the east riding for the noise it made. HA!
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